O'Brien says here that his mother died two years earlier, yet in TNG's "Family" - set four years ago - he said that he once found his father chasing a nurse around sickbay. So his father did this while his wife was still alive?

Plotline

Returning from a meeting with the Paradan government, Miles finds that everybody on the station is acting strangely toward him. Fearing a terrible conspiracy may have gripped the whole of Starfleet, he runs for his life with his former friends in close persuit.